Machine-tool transmission and control



2 Sheets-Shem l .Fm W

INVgTOR ATTORNEY April 7,. 1931. J. B. ARMITAGE E TOOL TRANSMIS MACHIN SION AND CONTROL Filed Sept 28, 1927 Ami? 7, 1931. .1. B. ARMITAGE MACHINE TOOL TRANSMISSION AND CONTROL Filed Sept. 28. 1927 2 Sheets-Sheet 2 INVENTOR a E ATTORNEY Patented Apr. '7, 1931 PATENT OFFICE .iosarn a. a'amrraea or' MILWAUKEE, Wisconsin, ASSIGNOR 'ro KEARNEY a rnnoxnn oonroaa'rron; or wnsr ALLIS, wrsoonsm momma-"root TRANSMISSION common a 1ition filed September 28,1227. Serial Ho. 222,513.

'llhis invention relates to. transmission and control mechanism for power relative movement of the work'and tool in amachine tool. Anobject 'ofthe invention is to provide an 5 improved machine tool transmission'mechanism and an improvedcontrol therefor, whereby several supports may be selectively moved at preferred feed and rapid traverse rates. Another object relates to transmission and control means for milling machines having several movable supports, whereby the support normally most used. is provided with individual control means for maximum convenience of operation, while a plurality of other supports, normally less used, are provided with combination control means of suitable convenience of operation but greater simplicity of construction. Anotherobjectis'to provide a plurality of rapid traverse-rates'for a machine tool and controlled in accordance with the choice of" plurality of supports is tube;

which of a moved.

as Another object is to provide improved transmission means for alternatively apply ing a feed' and a rapid traverse to drive a}- machine tool support with a minimum shockor strain when changing from the one to the other rate. 1

Another object is to provide, mechanism whereby suitable brake means may be applied at the instant of changing from a fast support movement to a slow support movement.

Other objects relate to t e simplification and improvement of the construction and operation of milling machines, others to a milling machine in which mechanism for one or more of the several purposes herein mentioned is provided in improved combination with other mechanism, and othcrs to the combination of mechanism previously mentioned with certain milhng machine structure to provide improved convenience or utility for the-combination.

With the above and otherobjects in 'view,

the invention consists of the novel features of construction,arrangement and combination of parts as herein shown and described and as particularly pointed out in theflclaims,

and insuch modifications as may be equiv.- alent to the structure claimed.

In the drawings, the same reference characters have been used to designate the same parts i-n'each of the views. XFig. 1 is a right side elevation of a knee and'colu'mn type of milling machine in which the invention is incorporated.

Fig. 2 is afront elevation of the same machine with portions broken away.

along li'ne3-3 of Fig. 2. i Fig. 4.is a developed partial section along line-4.4 of Fig. 2. v Fi 5is an enlar ed section alon one of the s afts shown in 'ig. 3 and mem rs associated therewith. Y

Fig; 6 is an end view of'the mechanism shown in Fig. 5 partly in section along line 6-6.1of Fig. 5.- i

Fig. 6A shows part of the mechanism of Fig. 6 in a different operating position.

Fig. 7 is a detail part in section.

Fig. 8 shows parts associated with a control shaft as will be described.

1 Figs. 9. and 10 are enlarged developmentsihowing the form of certain cams shown in column 1 rotatably supports a tool spindle 2 and a main drive pulley'3 forming a power source for the various transmissions of the milling machine. Column 1 also supports a table orwork support 4 which is movable relative to tool spindle 2 in three transverse paths by the means of a saddle or support 5,

which supports and guides the table for longitudinal horizontal movement, and a knee 6 which supports and guides the saddle for cross horizontal movement, and is itself supengagement. Different sized gears 15a, 15b, 150, are slidably keyed to shaft 10, to he shifted by meansincluding a pivoted hand lever 16 connected with a lever 17 having a pivoted'shoe or fork l8 engaging the sides of gear 156. They maythus be selectively engaged with gears 19, 20, 21, fixed on shaft 22.

The shaft 22 is connected to drive the spindle 2 by the means of gear 23 fixed on the spindle and pinion 22a fixed on the shaft. The mechanism just described constitutes a spindle drive train including a clutch and a rate changer by the means of which the spindle may be driven from pulley 3 at selected speeds or may remain idle.

The shaft 10 is extended and has fixed thereon the gears 24, 25, 26, adapted for selective engagement by gears 27a, 27 b, 270, which are slidably keyed to a shaft 28, and may be moved for such engagement by means including pivoted lever 29 connected with lever 30 which has a shoe or fork 31 engaging the sides of gear 27?). Shaft 28 drives a shaft 32, Figs. 1, 2, and 4, which isrotatably supported by the knee 6, through an extensible universal joint shaft generally denoted by the numeral 33 and of usual construction.

The mechanism described constitutes a feed train including a rate changer, whereby shaft 28 may be driven from pulley 3 at a selected feed rate, but only when the spindle- 2 is driven, since power is derived through the clutch 11. I

Gear 8 is fixed on a shaft 34, Fig. 1, and drives a shaft 35, Figs. 1, 2, 3, rotatably su ported in knee 6, through gears 36 and 3%,

shaft 38, and a collapsible universal joint of usual construction and generally denoted by the numeral 39. Such mechanism constitutes a constant speed rapid traverse train,.whereby shaft '35 may be driven whenever pulley 3 is rotated.

The feed shaft 32 may drive a sleeve 40 through mechanism as follows. A pinion 32a fixed .on shaft 32 drives a' gear 41 fixed on.shaft;42. See Fi 2, 3, 4, 5, of which Fig. 2 particularly s ows the relative position of the shafts. The sleeve .40 is;free to rotate on but is supported by shaft'42 and is driven from gear 41 for reasons which will appear later through an over-running clutch device generally denoted by the numeral 41a: of Fig. 5 whereby gear 41 may drive the sleeve, but power may not be transmitted in the other direction. The device 41: consists of a cam member or driver 41a, Figs. 5, 6, 6A,

fixed or integral with the extended gear hub,

and having a series of cam faces 41b spaced around the periphery and forming, with an interior bore or recess 40a of sleeve 40, a series of spaces or pockets each adapted to contain.

roll members 43. The roll Iii embers 43 are spaced and retained for simultaneous movement by the means of a cage member 44 which their fnvn r-ninfivn i'n "1111 link In? OPB'II nnnn which it is supported. A torsion spring 45 has one end 45a fixed in a suitable recess in gear 41 and the other end 456 in 'a similar recess in cage 44, the'arrangement being such that the spring tends to rotate the cage relative to cam member 41a in a direction to yieldingly force the rolls along the cam faces 41?), which have a rise suflicient to cause the rolls to move outwardly into contact with the interior of the bore 400. asa friction member tending to drive the sleeve 40 from feed shaft 32 unless the sleeve is rotated more rapidly in the same direction, in which case the rolls release their gripv and sleeve40 is free to turn independently.

Sleeve 40 may'also be driven from" quick traverse shaft 35 through the following mechanism. Rotatable on shaft 35 is a gear 46, Fig. 3, which may be clutched with the shaft to be driven therefrom by the means of a friction clutch generally denoted by the numeral 47 and having a shiftable spool or clutch engaging'member 48. Clutch 47 maybe of'any well known type and therefore is not shown or described in detail. Gear 46 meshes with a. gear 49a fixed on a sleeve 49 rotatable on a fixed stud 50. A gear 496 isjalso fixed on the sleeve 49 to rotate with gear 49a, the. gears 49b and 4901 being of different diameter. Complementary gears 51a and 51b'rotatably supported on a fixed stud 52 may move axially to engage one at a time with the gears 49a and 496 respectively and accordingly as the one or the other is engaged the gear. 51b will, if clutch 47 is engaged, be driven at either of two'quick traverse rates. Gear 516 in any position of its axial movement, meshes with a gear 40b fixed on sleeve 40.

The two quick traverse rates alternatively obtained through gears 49a and 496 each tend to revolve sleeve 40 in the same direction as the-feed drive but at a rate morerapid than the highest feed rate Thus, when clutch 47 is engaged, the rolls 43 of the over-running clutch device 41w disengage as previously explained and permit the'sleeve 40 to move at a quick traverse'rate, but immediately the "clutch. 47 is disengaged the speed of the sleeve is'.reduced and the device 41w again drives the sleeve at the feed rate.

When the rapid traverse and feed rates are alternated, the mechanisms usually employed subject the parts to great strain and shock, both when the driven parts are suddenly accelerated and when their rate is suddenly reduced to a feed rate. By the im proved mechanism here shown such shock is almost completely avoided in each instance. The rapid traverse rate is comparatively very gradually applied to the heavy supports, in part because of the well known nature of friction clutches and input because the position of clutch 47 in the train enables ad- Each roll then acts opposed and inter-acting surfaces.

vantage tobe taken ofv the torsional resiliency of the driving and driven shafts.

When the clutch is disengaged to engage the feed the rolls 43 will not act to retard the sleeve 40 or the, parts driven therefrom until the rate has been reduced: by friction to a feed rate.

employed, which takes effect the instant the clutch 47 is disengaged, by the means of the tinuously driven at a feed rate, whereby there is no retarding friction from the pressure of spring during feed movement of the supports, but when sleeve 40 is driven at a rapid traverse rate the parts described act as a brakewhichltends to slow the sleeve down to a feed rate immediately clutch 47 .disengages. Additional braking eflect' is had from the friction bf the rolls 43 against the interiorof bore 400, the sides of the slots in cage 44 and the cam surfaces 41?). The rolls cannot drive sleeve 40. during quick traverse movement but a continuous friction is maintained between the urfaces mentioned during such movement because the tendency of spring 45 is to force the rolls into the Wedge-shaped space'between the cam surface and the bore and immediately the clutch 47'is disengaged such friction is added to the friction mentioned above as an added brake retarding the parts to afeed rate, but

inoperative during feed movement.

Sleeve 40 may drive a table screw 54 through a train which is individualto the table consisting of a gear-"55, Figs. 4'and 1,

shaft 56, a bevel gear 57 slidably s plined on shaft 56 and movable with saddle 5, bevel gear 58 meshing therewith, shaft 59, gear 60 fixed thereon and drivinggear film-Fig. 2, through an idler (i2 and a reverser generally denoted by the numeral 63ineluding bevel gear 61?) fixed with gear 610: and the o apositely-disposed bevel-gears 64 and 65 meshing therewith. The screw 54' is journaled at its ends in table 4 but fixed against axial movement relative thereto in the usual manner and passes throughsuitable axial bores in gears 64, 65. Positioned between the gears is a clutch or reverser member 66 slidably keyed to the screw 54 and adapted to be oppositely shifted to clutch engagement with suitable clutch devices on the respective gears or to be centrally positioned, out of engagement with either gear, whereby member 66 and screw 54 T o reduce the time interval before this occurs; and thereby increase pro-u duction from the machine, a friction brake is may be driven in either direction or may be stopped. Screw 54 is in threaded engage-- table train operable from sleeve 40 independently of any other mechanism driven from the sleeve, and including means for independently reversing or stopping the table;

Sleeve 40 may drive the saddle 5 or knee 6 through, mechanism as follows. A stud 67,

Fig. 3 carries a clutch gear 68 meshed directly with gear 40a, and a clutch gear 69 driven from gear 406 through the gear 516,

which acts as an idler. Fig. '3 being a devel-- opment does not show the gears in mesh, but the relationship described may be clearly seen 'in Fig. 2 which shows the studs 67, 42, 52 in their true position. Thus gears 68 and 69 are oppositely driven. A clutch member 7 0b positioned between the gears may be shifted the one or the other direction to engage sultable clutch faces thereon with complementary clutch faces of the one or the other gear,

whereby the member 706 may be driven in either direction, and may also I be centrally positioned to remain stationary. The mecha nism just described constitutes a reverser and motion interrupter generally denoted by the numeral 71 whereby part-s driven from clutch member 706 may be driven in either direction or 'may be stop ed. Fixed on clutch member 706 is a gear 0.

A knee transmission may be driven from gear 70 consisting of a gear 72 rotatable and axially movable on a stud 73, and having projecting lugs or keys 720 engaging with complementaryv slots in the extended hub 74 of a bevel gear 75, which meshes with a bevel gear 7 6, Fig. 1, fixed on avertical screw 77 having threaded engagement with a'nut 78 fixed in an upstanding stum portion 1a of the base of column 1. Gear 2 may be moved to engage or disengage gear 70 and if engaged the knee may be driven in either direction or stopped by the reverser 71.

A saddle transmission may be driven from gear 70, as follows. A gear 79, Fig. 3,is slidably keyed on the shank of a screw 80, Figs. 1, 2 and 3. Gear 79 when in one position-of axial movement engages with gear 70. This may be easily seen from the relative position ofscrew SO-and stud 67 in Fig. 2, although Fig. 3,-being a development does not show the gears meshed. Screw 8O in threaded engagement with a nut 5a fixed with saddle 5, Fig. 1. Gear 79 may be moved to engage or disengage gear 7 O, and if engaged the saddle may be driven in either direction or stopped bythe reverser 71.

The transmission described consists of a portion common to both the saddle and knee and including reverser 71, and other portions is also fixed a individual to the knee and saddle respectively whereby either the knee or saddle may be driven .in either direction from the sleeve 40.

The several screws may each be hand operated for manual movement of the supports, the saddle screw andthe table screw 54 being provided with squared ends 80a and 54a respectively, and the vertical screw 77 having a ear 81 engaging gear 76 and fixed on' a shaft 82 having a squared end 82a, the several squared ends being adapted for a crank, not shown.

The table reverser 63 may be manually operated by the means of a hand lever 83, Fig. 1,

fixed on a shaft 84 upon which is also fixed a lever 85 having a pivoted shoe engaginga suitable annular groove 66a in the shift'able' is slidably supported in a suitable axial bore in the stud 50, upon which is slidably supported a sleeve 92 connected for movement with rod 91 by the meansof a pin 93 passing through the sleeve and rod 91, there being a suitable slot in the stud 50 to provide for the pin movementl Sleeve 92 is connected for movement with a fork 95 by themeans of a stud or rod 96 fixed in both members. The fork 95 has a sleeve slidably supported (in the sleeve which forms the hub connecting the gears 49a and 49b, and en ages with eachnulargroove 97 a in the shi table clutch member 97. The unbalanced weight of lever 90 tends to move the clutch member 97 out of engagement but is sufficiently overcome to prevent undesired disengaent by the means of a, spring 98 in the same bore which be shifted to -deguides rod 91.

The gears 79 and 72 ma termine whether the sadd e or knee is to he power driven, by' the means of the following mechanism. p v

A hand lever 99 is fixed on a shaft 100 which carries a cam member 101, Figs. 2, 2a, 8 and 10. Suitably positioned relative to the same member are the forks 102 and 103. Fork 102 is slidable on shaft 100 and has a portion 102a:

engaging an annular groove 79a, Fig. 3, in v the hub of gear 79. A cam follower pin 102b fixed in the sleeve of the fork operatively engages the cam groove 101a in the cam member. Fork 103 is slidable on the outsideof the cam member and has a portion 1030: en-

gaging an annular groove 72% lFig. 3. in the areaara hub of gear 72, A. cam follower pin 103 0 fixed in the sleeve of the fork also operatively engages the cam groove 101a. As shaft 100 is turned by thehand lever 99, the cam pins central position in which both gears are disengaged and neither the knee orsaddle receiv'es power. Thus the control mechanism has positions effective for actuating either the knee or saddle but not both, and a central position in which neither are actuated. Such positions are defined by the means of a spring plunger'99a associated with hand lever 99 and adapted to engage suitable configuration when the lever is positioned as described two of such configurations bein shown at 9915 and 990, Fig. 2A, the other eing hidden by the lever.

The described movement of lever 99 also simultaneously controls the shifting of the gears 51a 51b for selecting one or the other of the rapid traverse rates to be efiective when clutch 47 is engaged as follows. Shaft 100 has fixed thereon a cam member 10 1,

Figs. 2A 8, 9. An adjacent shaft 105 has fixed thereon a lever 106 provided with a cam or follower pin 107 engaging the cam groove 1040, of the cam member, and also fixed on shaft 105 is a lever 108 having a pivoted fork 109 engaging the sides of gear 51a. The form of cam groove 104a and relationship of the parts is such that when lever 99 is positioned centrally so that neither the knee or saddle may be actuated, the gear 510 isengaged with gear 9a whereby the faster of the two ra id traverserates is available to drive the ta 1e, but if the lever 99 is in either of its other positions whereby the knee or saddle may be actuated, then the gear 51?) is engaged to be driven from gear 496 and the slower of the .two rapid traverse rates is available to drive either the knee, saddle or table according to the shifting of the other control mechanism. Thus the table may be driven at either rapidtraverse rate but the knee and saddle may only be driven at theslower rapid traverse rate.'

What is claimed is:

1. In a milling machine having a vertically movable knee, a saddle movably supported on said knee and a table movably supported on said saddle, the combination of transmission mechanism for movement of said knee, saddle and table including a member shiftable to select different rates, said mechanism also including means shiftable to difierent positions for movement of said knee and saddle respectively and to another areaava position in which said transmission is inoperative for knee or saddle movement, and control mechanism including a connection between said member and said means and operative to prevent movement of said knee at the faster one of said rates.

2. In a milling machine, the combination of a rotatable tool spindle, a plurality of traverse train from actuating said device atone of said quick traverse rates when said shittable elements are in a predetermined position.

3. In a milling machine having a rotatable toolspindle, a knee member, a saddle memher and a table member each bodily movable relative to said spindle, a spindle drive including a power member anda clutch, transmission mechanism for movement of said members including elements relatively shiftable to select difierent of said members to be actuated from said transmission, said elements having a position selective of said knee and another position selective of said saddle and a third position inwhich only said table may be actuated, a feed train driven from said power member through said clutch and including a feed rate changer, a quick traverse train driven from said power member exclusive of said clutch -and' of said teed rate changer, said trains being alternatively connectible ior actuating said elements, said quick tra nrse train providing mechanism shittable for different quick traverse rates, and control means operable on the last mentioned mechanism in accordance with the position of said elements to prevent actuation of any otsaid elements at one of said quick traverse rates except when said elements are in said third position.

4. In a machine tool, having a movable support, the combination of transmission mechanism for said support including a feedv train, a rapid traverse train, and overrunning clutch means for alternatively connecting the one or the other of said trains to actuate said support including a plurality ofadjacent elements, one of which is connected to be driven from said feedtrain and the other connectible to be driven from said rapid traverse train, one of said elements cluding a friction member associated with said cam surfaces and means yieldably pressing said friction member to move alon said cam surface, said friction member dieing adapted for such movement thereof to cause simultaneous engagement of the friction member with each of said adjacentelements, said rapid traverse train providing motion interrupting means whereby to prevent either of said elements being driven at a rapid traverse rate during said simultaneous engagement.

5. llna milling machine, the combination of a rotatable tool spindle, a column support ing said spindle, a support member movably supported from said column, a table member supported on said support for horizontal movement in a path transverse to the axis of said spindle, a spindle transmission including a motion interrupting clutch and a speed rate changer, and transmission mechanism for actuating said members including a feed train providing a feed rate changer and driven through said clutch to exclude said speed rate changer, a quick traverse train unaffected by said clutch and by either of said rate changers and adapted to be operated at two different quick traverse rates, a transmission element, mechanism normally connecting said feed train to actuate said element and including an overrunning device, means for selectivel connecting or disconnecting said quic traverse train and said device, branch lines connectible with difierent of said members re spectively and each connected to be actuated from said element, and control mechanism including control means selective of the one or the other of said branch lines to actuate the member with which it is connectible, and control means operable to prevent operation of said element at one of said quick traverse rateswhen the first mentioned control means is'positioned to select said support-member for actuation.

6. lin a milling machine, the combination of a rotatable spindle, a work table associated with said spindle and bodily movable relative thereto in three mutually transverse paths, transmission mechanism for movement of said table including. a feed train providing a feed rate changer, a quicktraverse train driven to exclude said teed rate changer'and adapted to be operated at two different quick traverse rates, a transmission element, mechanism'normally connecting said feed train to actuate said element and including an overrunning device, means for selectively-connecting or disconnecting said quick traverse train and said device, a first branch line for connecting said element for movement of said table in a first one of said paths and including a first reverser, a second reverser operable from said element independently of said first reverser, a second branch line for rue connecting said second reverser for movement of said table in a second one of said paths, a third branch line for connecting said second reverser for movement of said table in a third one of said paths, and control mechanism including means determinative of which of said branch lines is to actuate said table, and means preventing actuation of said element at one of'said quick traverse rates during movement of said table either from said second or from said third branch line.

7. In a millin machine, the combination of a base, a rotata le tool s indle anda work support each supported rom said base and relatively bodily movable in a plurality of paths, a power member, a spindle driving train including said member, a rate changer and said spindle in the order mentioned, a transmission for said relative movement including a feed rate element and a quick traverse rate element each driven from said spindle train to exclude said rate changer, a feed train driven from said feed rate element and including an overrunning device, a plurality of branch lines respectively for said relative movement in different of said paths and each including a reverser, each of said branch lines being normally connected with said feed train through said overrunning device, and control mechanism for said transmission including means adapted to selectively connect said quick traverse rate element with said device or to disconnect it therefrom, and means for selective individual operation of said reversers.

8. In a milling machine, the combination of a rotatable tool spindle,'a work table,'said spindle and'table bein relatively bodily movable in a plurality 0 paths, a spindle drive including a power source, and a rate changer, and transmission and control mechanism for said bodily movementincluding a feed train driven from said power source and a quick traverse train driven from said power source to exclude said rate changer,=branch lines respectively for said bodily movement in respective of said paths, overrunning mechanism normally connecting said feed train to actuate a portion of both of said branch lines, means for operating each of said branch lines from said quick traverse train, and a reverser in one of said branch lines individually controlling direction of movement actuated from the last mentioned branch line, said transmission and control mechanism including means operative to efiect a difl'erent rate of quick traverse movement in the difi'erent paths.

9. In a machine tool the combination of a plurality of movable supports, and transmission and control mechanism for movement of said supports including a power source, a feed train driven from said source and including a rate changer, a quick traverse train driven from said source to exclude said rate changer, a plurality of branch lines respeca tool spindle rotatably supported from said column, a knee supported from said column for bodily vertical movement, a work table slidably supported on said knee for movement in a plurality of paths transverse to one another, and transmission mechanism for the movement of said table including a power member rotatably supported on said column,

a feed train driven from said member and including a feed element bodily movable with saidknee, a quick traverse train driven from said member and including a quick traverse element xbodily movable with said knee, a table transmission, overrunning mechanism normally connecting said feed element to actuate said table transmission and bodily movable with said knee, mechanism bodily movable with said knee and selectively operable to connect and disconnect said quick traverse element to operate said table transmission, said table transmission including branch lines respectively operative for table movement in I respective of said paths, one of said branch lines including a reverser bodily movable with said knee and individual to the table movement in the path operative from the last mentioned branch line.

11. In a milling machine, the combination of a rotatable' tool spindle, a base supporting said spindle, a work table supported from said base, said spindle and table being relatively bodily movable in a plurality of paths, a spindle train including a power source and a rate changer, transmission mechanism for said bodily movement and driven from said power source to exclude said rate changer and including a feed rate train, a quick traverse rate train, aplurality of branch lines respectively for movement in the respective paths, overrunning mechanism normally connecting said feed train for uni-directional actuation of a portion of both of said branch .lines, a plurality of reversers individual to the respective branch lines and adapted to selectively provide either direction of movement in either of said paths in spite of the uni-directional actuation of said branch line portions, means shiftable for connection of said branch lines to be actuated from said quick traverse train, and control mechanism crating said quick traverse connecting means, said transmission and control mechanism being adapted to effect said quick traverse at substantially diiferent rates in the respective 5 paths.

In wltness whereof Ihereto aflix my s1gna-' ture.

JOSEPH B. ARMITAGE. 

